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The special issue of the Journal of Basic Microbiology focuses on the diversity of fungi and their ecological roles, highlighting the various lifestyles and interactions of different fungal groups. The articles in this issue cover topics such as stress response in fungi, mutual symbiosis with plants, biocontrol properties, and molecular studies on phytotoxins. The research presented provides valuable insights into the diverse capacities of fungi in their ecological interactions within soil environments. [Extracted from the article]

Biofilm formation can lead to tolerance against stressors like antibiotics, toxic metals, salts, and other environmental contaminants. Halo‐ and metal‐tolerant bacilli and actinomycete strains isolated from a former uranium mining and milling site in Germany were shown to form biofilm in response to salt and metal treatment; specifically, Cs and Sr exposition led to biofilm formation. Since the strains were obtained from soil samples, a more structured environment was tested using expanded clay to provide porous structures resembling the natural environment. There, accumulation of Cs could be shown for Bacillus sp. SB53B, and high Sr accumulation ranging from 75% to 90% was seen with all isolates tested. We could, therefore, show that biofilms in a structured environment like soil will contribute to the water purification obtained by the passage of water through the critical zone of soil, providing an ecosystem benefit that can hardly be overestimated. [ABSTRACT FROM AUTHOR]

The Journal of Basic Microbiology's special focus on rhizosphere microbes explores the communities and functions of bacteria, fungi, and other microorganisms living around plant roots. The plant provides carbon through root exudates, attracting beneficial microbes that protect the roots from pathogens and aid in nutrient uptake. The issue includes research on agricultural sustainability, fungal interactions, rhizobial effects on soil fertility, and mycorrhizal seasonality, highlighting the importance of plant-microbe interactions in soil environments. [Extracted from the article]

The article titled "Special Focus: The Potential of Gram‐Positive Bacteria" explores the unique characteristics and potential of Gram‐positive bacteria. Unlike most bacteria, Gram‐positive bacteria have a thick cell wall with teichoic acids and lipoteichoic acids. This distinct cell biology affects their interactions with both living and non-living environments. The article highlights the prolific secondary metabolism of the Gram‐positive Actinobacteria, particularly the filamentous actinomycetes, which are known for producing antibiotics. The study also examines other Gram‐positive bacteria, such as Bacillus subtilis and lactobacilli, and their abilities to produce nanoparticles, betalain, and proteases. Overall, the article provides insights into the specific interactions and potential of Gram‐positive bacteria. [Extracted from the article]

Genetic manipulation for generating knock‐out experiments is essential in deciphering the precise function of a gene. However, dikaryotic fungi pose the inherent challenge of having two allelic versions of each gene, one in each nucleus. In addition, they often are slow‐growing and do not withstand protoplasting, which is why Agrobacterium tumefaciens‐mediated transformation has been adapted. To obtain knock‐out strains, however, is not feasible with a mere deletion construct transformation and screening for deletions in both nuclear copies. Hence, a convenient method using chemically synthesized dicer substrate interfering RNA (DsiRNA) for posttranscriptional interference of targeted mRNA was developed, based on the fungal dicer/argonaute system inherent in fungi for sequence recognition and degradation. A proof‐of‐principle using this newly established method for knock‐down of the volatile geosmin is presented in the dikaryotic fungus Tricholoma vaccinum that is forming ectomycorrhizal symbiosis with spruce trees. The gene ges1, a terpene synthase, was transcribed with a 50‐fold reduction in transcript levels in the knockdown strain. The volatile geosmin was slightly reduced, but not absent in the fungus carrying the knockdown construct pointing at low specificity in other terpene synthases known for that class of enzymes. [ABSTRACT FROM AUTHOR]

This article, published in the Journal of Basic Microbiology, focuses on the ecological diversity and biotechnological use of fungi. It highlights various types of fungi and their interactions with different organisms. For example, it discusses Ganoderma lucidum, a tree pathogen with fruiting bodies used in Chinese traditional medicine. It also mentions plant parasites like Fusarium and Pythium, as well as endophytic fungi found inside plant tissues. The article further explores parasitic fungi that target animals, such as nematode trapping Arthrobotrys and Cordyceps, which prey on insects. Additionally, it covers soil fungi, cold climate-adapted fungal diversity, mycoviruses attacking fungi, and the biotechnological use of the basidiomycete yeast Rhodotorula. Overall, the article aims to showcase the broad ecological distribution and biotechnological potential of fungi. [Extracted from the article]

Plant growth promotion has been found associated with plants on the surface (epiphytic), inside (endophytic), or close to the plant roots (rhizospheric). Endophytic bacteria mainly have been researched for their beneficial activities in terms of nutrient availability, plant growth hormones, and control of soil‐borne and systemic pathogens. Molecular communications leading to these interactions between plants and endophytic bacteria are now being unrevealed using multidisciplinary approaches with advanced techniques such as metagenomics, metaproteomics, metatranscriptomics, metaproteogenomic, microRNAs, microarray, chips as well as the comparison of complete genome sequences. More than 400 genes in both the genomes of host plant and bacterial endophyte are up‐ or downregulated for the establishment of endophytism and plant growth‐promoting activity. The involvement of more than 20 genes for endophytism, about 50 genes for direct plant growth promotion, about 25 genes for biocontrol activity, and about 10 genes for mitigation of different stresses has been identified in various bacterial endophytes. This review summarizes the progress that has been made in recent years by these modern techniques and approaches. [ABSTRACT FROM AUTHOR]

Summary: Although many fungi are known to be able to perform bioweathering of rocks and minerals, little information is available concerning the role of basidiomycetes in this process. The wood‐rotting basidiomycete Schizophyllum commune was investigated for its ability to degrade black slate, a rock rich in organic carbon. Mechanical pressure of hyphae and extracellular polymeric substances was investigated for biophysical weathering. A mixed ß1‐3/ß1‐6 glucan, likely schizophyllan that is well known from S. commune, could be identified on black slate surfaces. Secretion of siderophores and organic acids as biochemical weathering agents was shown. Both may contribute to biochemical weathering in addition to enzymatic functions. Previously, the exoenzyme laccase was believed to attack organic the matter within the black slate, thereby releasing metals from the rock. Here, overexpression of laccase showed enhanced dissolution of quartz phases by etching and pitting. At the same time, the formation of a new secondary mineral phase, whewellite, could be demonstrated. Hence, a more comprehensive understanding of biophysical as well as biochemical weathering by S. commune could be reached and unexpected mechanisms like quartz dissolution linked to shale degradation. [ABSTRACT FROM AUTHOR]

The Journal of Basic Microbiology has published a special issue on pathogenic microorganisms. The issue includes articles on human pathogenic bacteria, fungi, and viruses, as well as the use of biocontrol organisms to prevent crop loss and reduce the use of plant protection agents. The issue also addresses the antimicrobial resistance crisis, dormant states of pathogens, biofilms, and fungal infections. Additionally, the issue explores the impact of viruses on human health and the threat of plant viruses to crop production. The articles aim to enhance understanding of pathogenesis in humans, animals, and plants. [Extracted from the article]

This article is a special issue of the Journal of Basic Microbiology focusing on soil microbiology and agriculture. It discusses the challenges of studying soil microbes and their interactions, including the effects of calcium ions and metal stress on microbial communities. The article also explores the interactions between soil microbes and plants, ranging from beneficial symbioses to pathogenic relationships. Additionally, it highlights the potential of bacteria and mycorrhizal interactions in managing plant diseases and protecting against environmental stresses. The goal of the special issue is to contribute to a better understanding of the soil environment and its microbial interactions. [Extracted from the article]

The Journal of Basic Microbiology has published a special issue on cell biology and biotechnology. The issue explores the connection between special structures and developmental stages in bacterial and fungal microorganisms, and their production of secondary metabolites that can be beneficial for human use. Topics covered include the production of antibiotics in streptomycetes, the use of pigments in bacterial and fungal strains, motility in Gram-negative proteobacteria, subtilisin production in a human pathogenic fungus, the development of chlamydospores in a nematophagous fungus, the involvement of a developmental regulator in the production of antitumor compounds in a phytopathogenic fungus, the control of antibiotic expression in Streptomyces, the exploration of metabolites in Nocardiopsis, the antimicrobial effects against coral disease, the use of a fungus as a biological control agent against ticks, and the enzymes involved in wood degradation in a white-rot fungus. The special issue aims to be of interest to researchers in biotechnology and microbiology. [Extracted from the article]

Summary: The regulator of G‐protein signalling, Thn1, is involved in sexual development through pheromone signalling in the mushroom forming basidiomycete Schizophyllum commune affecting hyphal morphology and mating interactions. Thn1 plays a key role in coordinating sesquiterpene production, pheromone response and sexual development. The gene thn1 is transcriptionally regulated in response to mating with a role in clamp cell development and hydrophobin gene transcription. Further, it negatively regulates cAMP signalling and secondary metabolism. Disruption of thn1 affects dikaryotization by reducing clamp fusion and development with predominant non‐fused pseudoclamps. Enhanced protein kinase A (PKA) activities in Δthn1 strains indicate that Thn1 regulates pheromone signalling by de‐activating G‐protein α subunits, which control cAMP‐dependent PKA. The repressed formation of aerial hyphae could be linked to a reduced metabolic activity and to a transcriptional down‐regulation of hyd6 and sc3 hydrophobin genes. Thn1 was also shown to be necessary for the biosynthesis of sesquiterpenes and an altered spectrum of sesquiterpenes in Δthn1 is linked to transcriptional up‐regulation of biosynthesis genes. Proteome analysis indicated changes in cytoskeletal structure affecting actin localization, linking the major regulator Thn1 to growth and development of S. commune. The results support a role for Thn1 in G‐protein signalling connecting development and secondary metabolism. [ABSTRACT FROM AUTHOR]

With this Special Issue, we come back to interactions of microbes with plants. Not only mycorrhizal symbiosis is a major plant growth-promoting feature depending on microorganisms, but also rhizosphere, phyllosphere, and endophytic bacterial and fungal associations with plants can lead to protection against pathogens as well as growth promotion. The plant growth promotion in addition to biocontrol can lead to higher resilience of plants, which is featured by Devindrappa et al. (this issue). [Extracted from the article]

Material properties at small scales may change, like titanium oxide nanoparticles being transparent, while the bulk particles of titanium oxide are white. Here, metals and metal oxide nanoparticles are reviewed by Mukherjee et al. (this issue). Nanomaterials, of which nanoparticles are a subset, are defined merely by size, usually referring to materials with at least one dimension having a size of 1-100 nm. [Extracted from the article]

Microbial communities in soil, groundwater, and rock of two sites in limestone were investigated to determine community parameters differentiating habitats in two lithostratigraphic untis. Lower Muschelkalk and Middle Muschelkalk associated soils, groundwater, and rock samples showed different, but overlapping microbial communities linked to carbon fluxes. The microbial diversities in soil were highest, groundwater revealed overlapping taxa but lower diversity, and rock samples were predominantly characterized by endospore forming bacteria and few archaea. Physiological profiles could establish a differentiation between habitats (soil, groundwater, rock). From community analyses and physiological profiles, different element cycles in limestone could be identified for the three habitats. While in soil, nitrogen cycling was identified as specific determinant, in rock methanogenesis linked carbonate rock to atmospheric methane cycles. These patterns specifically allowed for delineation of lithostratigraphic connections to physiological parameters. [ABSTRACT FROM AUTHOR]

These range from rhizosphere bacteria and fungi, cover endophytes, and integrate plant biomass degradation. As for the rhizosphere, biocontrol fungi like I Trichoderma i may exert plant growth promoting as well as pathogen protective traits on plant growth (Valan Arasu et al., this issue). With this special issue, we want to address plant-associated microorganisms and their potential use. [Extracted from the article]

Due to the antibiotics crisis now, with increasing multi-resistant bacterial pathogens arising, a renewed interest in phage biology including the potential application of bacteriophages in phage therapy ensues. With respect to phages, this issue consequently includes the analysis of phages infecting (multi)resistant bacterial pathogens like a bacteriophage isolated and characterized for its potential to be used against shigatoxigenic I Escherichia coli i (Inbarai et al., this issue) or a phage infecting I Vibrio cholerae i (Maina at al., this issue). With this special focus on viruses and phages and their impact on different ecosystems, we hope to contribute to the rising interest in viral ecology. [Extracted from the article]

Despite the rising interest in microbial communication, only few studies relate to mycorrhization and the pool of potential morphogenic substances produced by the surrounding soil community. Here, we investigated the effect exerted by the C18-ketone β-apo-13-carotenone, D'orenone, on the ectomycorrhizal basidiomycete T richoloma vaccinum and its symbiosis with the economically important host tree, spruce ( P icea abies). D'orenone is an early intermediate in the biosynthesis of morphogens in sexual development of mucoromycetes, the trisporoids. In the ectomycorrhizal fungus T. vaccinum, D'orenone increased the production and/or release of the phytohormone indole-3-acetic acid ( IAA) which had been proposed to be involved in the mutual symbiosis. The induced expression of the fungal aldehyde dehydrogenase, Ald5 is associated with IAA synthesis and excretion. In the host tree, D'orenone modulated root architecture by increasing lateral root length and hypertrophy of root cortex cells, likely via changed IAA concentrations and flux. Thus, we report for the first time on carotenoid metabolites from soil fungi affecting both ectomycorrhizal partners. The data imply a complex network of functions for secondary metabolites which act in an inter-kingdom signalling in soil. [ABSTRACT FROM AUTHOR]

The lowering of meat production will positively effect greenhouse gas emissions, and to replace protein intake from meat, mushrooms may provide a good alternative. The changing world with effects of climate change is becoming more and more visible, also for sustaining world's population, and warrants a closer look into the potential that is held by microbes. A new interference between the hedgehog mushroom and the host endophyte community was shown by Zhang et al. (this issue) relating to interference with potentially plant growth promoting microbes. [Extracted from the article]

Ectomycorrhizal symbiosis is important for forest ecosystem functioning with tree-fungal cooperation increasing performance and countering stress conditions. Aldehyde dehydrogenases (ALDHs) are key enzymes for detoxification and thus may play a role in stress response of the symbiotic association. With this focus, eight dehydrogenases, Ald1 through Ald7 and TyrA, of the ectomycorrhizal basidiomycete Tricholoma vaccinum were characterized and phylogenetically investigated. Functional analysis was performed through differential expression analysis by feeding different, environmentally important substances. A strong effect of indole-3-acetic acid (IAA) was identified, linking mycorrhiza formation and auxin signaling between the symbiosis partners. We investigated ald1 overexpressing strains for performance in mycorrhiza with the host tree spruce ( Picea abies) and observed an increased width of the apoplast, accommodating the Hartig' net hyphae of the T. vaccinum over-expressing transformants. The results support a role for Ald1 in ectomycorrhiza formation and underline functional differentiation within fungal aldehyde dehydrogenases in the family 1 of ALDHs. [ABSTRACT FROM AUTHOR]

Overproduction of secondary metabolites requires know-how for media optimization and design of effective screening procedures. Micro-segmented flow was applied to test the growth characteristics of heavy-metal tolerant soil bacteria ( Bacillus sporothermodurans and Streptomyces tendae) toward changing media composition. The applied microfluidic technique was shown to be suitable for media optimization, with effects of media solutes like phosphorus and nitrogen, and a trace metal solution. For inorganic phosphate and trace metals, the synthesis of secondary metabolites had a much narrower tolerance for concentration ranges than vegetative cells. As we worked with metal-tolerant strains, some tests were done in the presence of copper-II ions in the bacteria-specific critical concentration of 0.25 mM. In particular, for the Bacillus strain, the macronutrient phosphorus resulted in a threefold increase in growth with rising concentration. Copper led to a prolonged lag phase. For S. tendae, no similarly enhancing effect was observed. The trace metal solution promoted bacterial growth only in the case of S. tendae, for higher concentration ranges. For the nitrogen source, especially S. tendae responded with changes between the light scattering and the fluorescence signal. This could be a hint for the production of fluorescent secondary metabolites. [ABSTRACT FROM AUTHOR]

The formation of soil organic matter (SOM) has been proposed to depend on fragmentation of biomass after cell death. However, this is hard to mimic in laboratory experiments showing the process directly. We used heavy metal contamination in order to provide an environment in which one Streptomyces strain, the heavy metal resistant S. mirabilis P16B-1, could survive while the sensitive strain S. lividans TK24 was expected to die and disintegrate; the necromass fragments would then contribute to SOM formation. Both strains were grown for 30 d in sterile mesocosms containing either highly metal-contaminated soil from a former uranium-mining site in Ronneburg, Germany, or control soil from a municipal park, Jena, Germany. The fate and morphology of living and dead bacterial biomass (necromass) was observed using scanning electron microscopy. Attachment of soil particles to the intact mycelium as well as decay of dead biomass was observed. Dead bacterial biomass was identified in form of patchy fragments while the superordinate filamentous structure of the hyphae was still visible and obviously stabilized in soil. The fate of cytosolic compounds was followed using the example of a nickel-containing superoxide dismutase (NiSOD) which was found to be released after death of cells grown in liquid soil-extract medium. Activity of the enzyme was proven for concentrated media supernatant by a gel-based qualitative activity assay. This indicates that NiSOD remains active in soil after cell death. Hence, bacterial cell death results in the release of cytosolic compounds, e.g., intact proteins, as well as the formation of residual cell-envelope fragments contributing to SOM formation. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) are integral functioning parts of plant root systems and are widely recognized for enhancing plant growth on severely disturbed sites, including those contaminated with heavy metals. However, the generality of detailed patterns observed for their influence on various metals and oxidative-stress parameters in multiple plant species is not clarified. The goal of this study was to investigate the patterns of metal-stress alleviation by AMF in four plant species. For this purpose, clover, sunflower, mustard, and phacelia were inoculated with Glomus intraradices and compared to noninoculated plants grown under heavy metal-stressed conditions. The study focused on the effect of AMF inoculation on plant biomass, assimilating pigments, total protein, superoxide dismutase and peroxidase activity, lipid peroxidation and As, Cd, Co, Cu, Fe, Mn, P, Pb, U, and Zn contents. As a result of inoculation very different patterns of variation were obtained for concentrations of elements and for biochemical parameters in plants. The particular effect of AMF inoculation on plants was species- and metal-specific, although there was a general enhancement of plant growth. [ABSTRACT FROM AUTHOR]

Heavy metal contamination of soil has an immense impact on the surrounding environment, such as the ground water, and hence, has become an important issue within bioremediation. Therefore, heavy metal contamination has to be determined preferably cost-efficiently, rapidly, and reliably. Here, soil bacteria of the genus Streptomyces are used as bioindicators for heavy metal contamination investigated via micro-Raman spectroscopy. A single cell approach is studied to avoid time-consuming culturing and plate counting. Bacteria of Streptomyces galilaeus were incubated in Ni2+ enriched media and single cell spectra were recorded. Supervised statistics linear discriminant analysis was used to evaluate the influence of the culture age and the anion on bacterial cells, which has been determined to be minor compared with the spectral impact of Ni2+. The identification of the Raman spectra according to different Ni2+ concentration ranges is accomplished with a prediction accuracy of about 88%. Therefore, we conclude that Streptomyces can be used as a bioindicator to predict Ni2+ concentrations in the micromolar range. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Large numbers of bacterial and fungal endophytes have been reported from different plant tissues: roots, nodules, leaves, flowers and sprouts of legumes, with numbers ranging from few to more than 150. Endophytes can accelerate seedling emergence, promote plant establishment under adverse conditions and enhance plant growth. Endophytic microbes promote plant growth by helping plants in acquiring nutrients, e.g. via nitrogen fixation, phosphate solubilization or iron chelation, by preventing pathogen infections via antifungal or antibacterial agents, by outcompeting pathogens for nutrients by siderophore production, or by establishing the plant's systemic resistance. Further growth promotion is affected by producing phytohormones such as auxin or cytokinin, or by producing the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which lowers plant ethylene levels. For establishment of endophytes in different tissues, endophytic microbes must be compatible with the host plants and able to colonize the tissues of the host plants without being recognized as pathogens. A particular bacterium or fungus may affect plant growth and development using one or more of these mechanisms, and they may use different mechanisms at various times. The population density of endophytes is highly variable, depending mainly on the microbial species and host genotypes, developmental stage and environmental conditions. Genotypic and cultivar specific endophytes have also been reported. The quantum benefit derived by plants from an endophyte and vice versa is still not clear. It seems that the endophytic genus or species best adapted for living inside a plant is naturally selected. Here, we concentrate on soil or rhizosphere-derived endophytes recruited out of a large pool of soil or rhizospheric microbes. Some endophytes are more aggressive colonizers and displace others, but seeming lack of strict specificity has been observed. However, the processes of host-microbe signaling and colonization and the mechanisms leading to mutual benefits are less-well characterized. It is still not clear which population of microorganisms (endophytes or rhizospheric) promotes plant growth and the way the interactions among endophytes influence plant productivity. Though attempts to know the molecular ecology and interactions are underway, a high amount of progress is required to fully understand the mechanism of establishment, the way interactions take place in planta, between different microbes and plants and exlusive benefits by endophytes and plants. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Every organism can be characterized by the amino acid composition of its proteome. So far it was assumed that these compositions are determined by the GC content of the DNA or, in some cases, by extreme lifestyles, like thermophily or halophily. Here, we focussed our analysis on eight amino acids, each of which is encoded by both, GC and AT rich codons, to identify finer amino acid patterns beyond the GC dominance. We investigated the conceptually translated proteomes of 1029 bacterial and archaeal strains with sequenced genomes for amino acid composition. Using correspondence analysis, we found that phylogenetic groups within bacteria and archaea generally can be discriminated from other groups due to their amino acid composition. In some cases, single organisms, e.g. Treponema pallidum strains or Mycoplasma penetrans, are characterized by extreme amino acid compositions. We assume that our data could provide a basis for a new approach to analyze evolution of bacterial and archaeal groups. Furthermore, for single organisms, the detailed knowledge of the amino acid composition of the entire proteome encoded in the genome could lead to a better understanding, important for pharmaceutical or biotechnological applications. We recommend that information about amino acid compositions should be provided in databases, comparable to the GC content of genomes. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

From seawater and the intestines of benthonic organisms collected from the Beagle Channel, Argentina, 230 marine bacteria were isolated. Cultivable bacteria were characterized and classified as psychrotolerant, whereas few isolates were psychrophiles. These isolates were capable of producing proteases at 4 and 15 °C under neutral (pH 7.0), alkaline (pH 10.0) and acidic (pH 4.5) conditions on different media, revealing 62, 33 and 22% producers at cold and 84, 47 and 33% producers at low temperatures, respectively. More protease-producing strains (67%) were detected when isolated from benthic invertebrates as compared to seawater (33%), with protease production under neutral conditions resulting in milk protein hydrolysis halos between 27 and 30 ± 2 mm in diameter. Using sterile 0.22 μm membrane filters, 29 isolates exhibiting extracellular protease activity were detected. These were grouped into six operational taxonomic units by restriction analysis and identified based on 16S rDNA as γ-proteobacteria of the genera Pseudoalteromonas, Pseudomonas, Shewanella, Alteromonas, Aeromonas, and Serratia. Plasmids were found to be harbored by eight strains, mainly within the isolates from benthonic organisms. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The article focuses on a study that aims to predict the potential metallothioneins and metallohistins in actinobacteria which are both short peptides with high cysteine and histidine content. It notes that 73 sequenced actinobacterial genomes were used in the study and were monitored for heavy metal related clusters or operons. Results of the study claimed that there were similarities on the metal binding protein domains, including zinc fingers and metal transporters.

46 actinomycetes were isolated from two polluted sites and one unpolluted site. One strain, F4, was selected through primary qualitative screening assays because of its cadmium resistance, and physiologically and taxonomically characterized. F4 was able to grow at 7.5% NaCl and 100 μg/ml lysozyme and at a pH between 6 and 10. 16S rDNA sequence analysis showed that F4 was closely related to Streptomyces tendae. Growth of Streptomyces sp. F4 on culture medium with 8 mg/l Cd for 8 days showed 80% inhibition. Maximum specific biosorption was 41.7 mg Cd/g dry weight after 7 days of growth and highest Cdconcentration was found in the cell wall (41.2%). The exopolysaccharide layer only contained 7.4%, whereas 39.4% of Cd was found in the cytosolic fraction. Twelve % was found in the ribosomes and membrane fraction. This was verified with TEM, showing Streptomyces sp. F4 cytoplasm with dark granulate appearance. This study could present the potential capacity of Streptomyces sp. F4 for Cd bioremediation. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The article discusses the in silico analysis method in studying the distribution of genes coding for NiSOD in other taxa. It states that data mining has revealed homologous proteins from actinobacteria, proteobacteria, and chlamydiae thus allowing a comparison of protein structural elements. To detect putative accessory enzymes in maturation, genomic sequences surrounding genes encoding NiSOD homologs were compared. It found an endopeptidase gene linked to sodN in actinobacteria and cyanobacteria, but not in other taxa.

The article presents a study on the bioaccumulation by the actinobacterium Amycolatopsis sp. ABO. The ability of the microorganisms to accumulate and immobilize toxic metals are vital for the bioremediation of polluted environment. Amycolatopsis sp. ABO has shown to be the most copper resistant strain among 50 actinobacteria isolated from polluted and non- polluted sediments. Subcellular fractioning assays and Timm's reagent technique were utilized to confirm metal acumulation in growing cells of Amycolatopsis sp. ABO. It concludes that Amycolatopsis sp. ABO is an alternative for the removal and recovery of copper from contaminated wastes, thus, it can help to concentrate and immobilize the metal within the cell and decrease overall metal bioavailability in the copper polluted soil.

The article presents the study conducted regarding the behavior of microorganisms on the metallomorphic environments. The study of the impact of microbial behavior on minerals and mining areas geologically significant compounds has resulted to the understanding of the metallic elements cycle, stability and formation of biotopes and altered compounds. The microorganisms metabolic process is due to the dissolution of minerals which add to the formation of mineral deposits over geogical period. On the other hand, the effect of metals on microorganisms can influence habitat development.

The enhanced understanding of microbial cells as producers of such technologically interesting substances or processes has opened the road to go one step ahead and directly use the microorganisms as factories for production of goods that are not produced naturally by these same cells. Biotechnology using microbes for production of enzymes, natural compounds, or the transformation of chemical molecules - including the degradation of environmentally detrimental substances - has proven to be a strong tool for industry. Here we present some of the producers and their optimization with a review on halophilic lipases (Qiu et al., this issue). [Extracted from the article]

In addition to active motion, cell differentiation is a trait required for biofilm growth. Already the motion towards and attachment to this source of nutrition will foster formation of a first step in biofilm evolution, and therefore is included in this Special Focus. With this Special Focus, we would like to highlight the structuring of the environment provided with a solid surface. [Extracted from the article]

The vaccination has started now, and research with the new types of mRNA vaccines clearly has been essential to make this vaccination possible at such a short time after first detection of human infection by covid-19. With this special focus issue, we are glad to be able to present a selection of three reviews and one research article focusing on human pathogens. Here, the review by Khoshbayan et al. (this issue) is addressing diabetes patients that are more prone to acquire a mucormycosis even with cerebral invasion. [Extracted from the article]

Microbes interact in their natural environment constantly, among each other, with plant or animal hosts, and with the environment adjusting to different stresses. Within interaction with the host plant, the response of plants to fungal attack leads to release of plant-derived defense molecules, including allicin known as the tear-inducing onion odour. In plant protection, plant growth promoting microbes are increasingly used to minimize use of plant protection chemicals in agriculture. [Extracted from the article]

With this Special Issue, the journal shows the wide application of microbial systems. As we know, many microbes respond to other strains with specific metabolic features. Last, but not least, bio-prospecting is essential to identify new strains with specific features that may be exploited in biotechnology (Sahli et al., this issue). [Extracted from the article]

This might well be due to the easier distinction of interbreeding with insects as compared to fungi, and thus the valid species description is limited in fungi owing to the fact that the definition of species is based on a population that is interbreeding, and separated from other species. The lichen symbiosis already shows that fungi are also prone to undergo interactions with plants, in symbiotic, commensal or pathogenic symbioses. One such large protein encoded by the pks1 gene has been targeted with real time PCR for detection and quantification in an ascomycete fungus (Gherbawy et al., this issue). [Extracted from the article]

With this issue, a Special Focus is placed on biofilms. A research paper focuses on the connection between quorum sensing and biofilm formation, and the eff ect of nanoparticles (Gopalakrishnan et al., this issue). As bacterial mixed biofilm example, a biocorrosion biofilm formed by I Bacillus subtilis i and I Pseudomonas aeruginosa i is part of this Special Focus issue (Wadood et al.). [Extracted from the article]